1. Field of the Invention
The present invention relates to a filtering method for retrieving a desired piece of content from many pieces of content, a filtering apparatus by the filtering method, and a recording medium having a filtering program recorded thereon.
2. Description of the Related Art
Widespread use of personal computers and broadband provides an increasing number of opportunities to view or browse many pieces of content to users. For example, it is possible to acquire content data about music, movies, dramas, and novels by using download services or through online shopping or to make use of Web pages or blogs publicized by personals or images photographed by personals with digital cameras by using personal computers.
However, an increase in the number of pieces of content makes difficult for the users to browse all the pieces of content. In addition, it is necessary to prepare a method of easily retrieving pieces of content desired by the users.
Under such circumstances, for example, the following methods are proposed:
(A) Collaborative Filtering
For example, when a book is purchased through online shopping, purchase histories of other users are utilized to introduce other books purchased by the users who purchased the book.
(B) Tag
Tag information is added to pieces of content. A tag added to a specified piece of content is used as a keyword to retrieve other pieces of content.
In the case of (A), users can find other related pieces of content (books) only by selecting a piece of content (a book to be purchased). In the case of (B), since the tag is used as a keyword, it is easy to determine why the other pieces of content are selected.
Documents in related art include, for example, Japanese Unexamined Patent Application Publication No. 2002-334257 and Upendra Shardanandand Pattie Maes, 1995, “Social Information Filtering: Algorithms for Automating Word of Mouth”, ACM CHI'95 Proceedings.